This invention relates to a rotary steam boiler, which is an improvement with respect to the boiler disclosed in U.S. Pat. No. 4,165,615 issued Aug. 28, 1979 to Paune Morcov. The patent describes and claims apparatus for increasing the pressure and temperature of exhaust steam from the turbine in power stations.
The conventional condenser is eliminated because it requires a lot of water (60-100 times as much as steam).
This first apparatus comprises at least one pair of contrarotating drums each containing spirally coiled pipe and located within a casting so that succesive sections of each drum pass in sequence through one heated zone (2 quadrants) a neutral zone and a cooled zone. As a result of the temperature rise in the hot sector and an exchange of steam between the two drums, the pressure increases until it reaches its required value. This is the only method to increase the pressure of a gas in a "isochore" way, with the usual temperatures (700.degree.-800.degree. C.) that can be endured by the boiler material.
In the above mentioned patent the drum is provided with holes through which the steam passes from one section to another. Packings pressed hydraulically on the outer surface of the drum shaft are situated in the interior of the drums. Consequently they are not easily accessible. In the present application a single drum is provided in which lengths of spiral piping form a plurality of individual sections which are spaced around a central rotatable hollow shaft which is provided with ducts interconnecting the sections, and which has a receiver-head at one end and an outlet head at the other end. The new construction is more solid, simple and consequently more reliable. The third sector disclosed in the above-mentioned patent has been eliminated. It has been replaced by a low-pressure chamber which functions as an air-preheater and raises the thermic efficiency.